Gas operated wire rope driven catapult



March 1, 1960 H. BLESS GAS OPERATED WIRE ROPE DRIVEN CATAPULT Filed Jan. 14, 1957 f/y/ aw s 2,926,871 GAS OPERATED WIRE ROPE DRIVEN CATAPULT Harold Bless, Philadelphia, Pa., assignor to the United States of America as represented bythe Secretary of the Navy Application January 14, 1957, Serial No. 634,127

4 Claims. Cl. 244-63) (Granted under Title 35, US. Code (1952), sec. 266) The invention described herein maybe manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

This invention relates to means .for launching an aircraft and to means for providing a novel hook-up arrangement from the power piston of a launching catapult to the launching shuttle.

Prior art catapult systems comprised either hydraulic drive or gaseous drive with a slotted cylinder tube for the power piston. With the hydraulic catapults, the structure becomes massive and very heavy; in addition, the efficiency of such catapults is very low at higher energy ranges. On the other hand, the slotted cylinder tube type of catapults are difiicult to maintain because of seal difiiculties in the tube slot; likewise, they tend toward heavy structures because of structural appurtenances to hold the tube slot configuration.

The object of this invention therefore is to provide a launching system wherein the power launching piston acts within an enclosed cylinder at all times.

A further object of this invention is to provide a launching unit which provides a two-way cable hookup from a gas driven power piston to the launching system.

These and other objects will be readily apparent from an examination of the following specification and attached drawing wherein:

The single figure depicts the novel catapult system.

In the figure, power piston 10 rides in a cylinder 16. Because of its extreme length, cylinder 16 is comprised of a plurality of sections 16' fastened together to form a continuous tube for the piston. At the forward end of the cylinder, exhaust means 18 and inlet means 17 are connected thereto serving as the means of ingress and egress for the gaseous motive fluid, i.e. steam or compressed air. The standard valves are also provided in each of the connections.

Cylinder 16 is closed at each end by a wall 20 to prevent the loss of the motive fluid only the wall 20 at the forward end of the cylinder being shown. Secured to each wall 20 are a pair of cable seals 8. A pair of tow cables 6 are attached to the forward or muzzle face of the piston 10 and pass through the seals 8. Each tow cable has a plurality of pulleys 21 which properly align the cables with the shuttle 3 and aid in tensioning the cables. The tension of the cables is adjusted by tensioners and cable equalizers 7 each of which consists of a pulley mounted in a housing 22 and which housing is attached to a shaft 23. The shaft is reciprocated by a hydraulic motor 15; the motors 15-15 are interconnected by a conduit 25 to produce a hydraulic balancing action between the cable equalizers thereby maintaining equal tension in the tow or launching cables 6.

After being reeved over the pulleys 21, each tow cable 6 passes adjacent to slot in the flight deck 19 and is connected to the shuttle 3.

At the opposite end of the shuttle are attached a pair 2,926,871 Patented Mar. 1, 1960 of closing cables 24 which lead back to the breech face of the piston 10 via idler pulleys 1, 2, slack eliminators andcable equalizers 12, 14 and cable seals 8 similar to the tow cable connections. In addition, the closing cables 24 are passed through a retraction engine 11 which operates to retract the piston to its firing position. Slack eliminator motors 14 are pressurized from a common accumulator 26 via conduits 27 to maintain equal and nearly constant tension in the closing cables regardless of stretch.

0n the same side of the shuttle as closing cables 24 are also attached a pair of brake cables 13 which are reeved over pairs of pulleys 28 and 30 and are connected to the braking and retracting engine 4. The latter engine not only brakes the shuttle but also assists the engine 11 in retracting the shuttle and piston to their firing positions.

In operation, the tow cables 6 are properly tensioned and their lengths equalized by adjustment of tensioners 7. Likewise the closing cables 24 have their slack eliminated and are tensioned by adjustment of motors 14 attached to slack eliminators 12. The piston in its retracted state is adjacent inlet and outlet connections 17, 18 of the cylinder. Steam (or compressed air) is admitted at the inlet 17, which steam expands to shoot the piston rearwardly; the shuttle 3 is accelerated forwardly by the tow cables 6 thus launching the aircraft (not shown) which is attached to the shuttle by a cable (not shown). At the same time that the tow cables 6 are pulling shuttle 3, the shuttle in turn is pulling closing cables 24 maintaining them taut. After a predetermined length of travel of the shuttle, it is braked by the braking engine 4. The standard valve in connection 17 is closed simultaneously with the opening of exhaust valve in outlet connection 18; retracting engines 4 and 11 are then actuated to return the piston and shuttle back to their firing positions for a repetition of the cycle just described.

Obviously many modifications and variations of the present invention are possible in the light of the above.

teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

What is claimed is:

1. In a catapult for launching aircraft from the flight deck of an aircraft carrier or the like having a slot therein defining a fixed path, the combination comprising a shuttle member movable in opposite directions along said fixed path, an elongated cylinder adapted to admit and exhaust pressurized fluid adjacent one end thereof and having a plurality of apertures in the end walls thereof, a piston slideably carried within said cylinder and being movable therein in opposite directions, said piston being movable in one of said directions when pressurized fluid is admitted to said cylinder and being movable in the other of said directions when pressurized fluid is exhausted from said cylinder, a plurality of tow cables connecting said shuttle member and one end of said piston and extending through said apertures in one of said end walls of said cylinder, said tow cables being operable to pull said shuttle member in one of said directions along said fixed path when said piston is moved in said one direction in said cylinder, seal means carried in said apertures in said one end wall of said cylinder and being cooperable with said tow cables to prevent the leakage of pressurized fluid from said apertures in said one end wall of said cylinder, a plurality of pulleys slideably supporting said tow cables intermediate said shuttle member and said piston and being operable to align said tow cables with said cylinder and said fixed path of movement of said shuttle member, a motor operated tensioning means acting on each of said tow cables to tension said closing cables to simultaneously pull said shuttle.mem

her in the other of .said directions along said fixed path and pull said piston in the other of said directions in said cylinder, seal means carried in said apertures in said other end wall of said cylinder and being cooperable with said closing cables to prevent the leakageof pressurized fluid from said apertures in said other end Wall of-said cylinder, a plurality of pulleys slideably supporting said closing cables intermediate said piston, said retraction engine and said shuttle member and being operable to align said closing cables with said cylinder, said retraction engine and said fixed path of movement of said shuttle member, a motor operated tensioning means acting on each of said closing cables to tension said closing cables and thereby prevent the formation of'slack therein, means connecting said tensioning means to substantially equalize the tension in each of said closing cables, and a combination braking and retraction engine operatively connected to said shuttle member for applying a "braking "force to said shuttle member during the .movement thereof .in said one direction .along said fixed path and for applying a retracting force to said shuttle member when said shuttle member is being pulled along said fixed path in the other of said directions by said first mentioned retractionengine.

2. In an aircraft launching system as claimed in claim 1 wherein said cylinder is :comprised of .a plurality :of aligned cylindrical segments.

3. In an aircraft launching system as claimed in claim I wherein said motor operated tensioning means acting on each of said tow and closing cables is comprised of a pulley movable in opposite'directions in a fixed plane by a hydraulic motor.

4. In an aircraft launching system as claimed in claim 1 wherein'said combination braking "and retraction engine is connected to said shuttle member by a plurality of cables, said cables being aligned with said combination braking and retraction engine "and said 'fixe'd path of movement of *said shuttle member by a plurality 13f pulleys.

References Cited in the file dfthis .patent UNITED STATES PATENTS 2,523,314 Maxson Sept. 26, v1950 FOREIGN PATENTS 480,692 Great Britain Feb. 25, 1938 

